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So. I like both, I have ideas for both. The question for you, who are more knowledgeable than I, is which is more competitive?
Applaud, my friend, the Comedy is finished.
Hive Fleet Charybdis (1-0-0) and Grey Brothers Space Wolf Chapter (3-1-2) [W-L-T]
Pick whichever you like the models of the most, after all that is what you are going to spend alot of time painting.
Lizardmen are the most balanced list, whereas Daemons have a reputation for being the most unbalanced list in 7th edition.
Deamons very Overpowered and the only army in the game that has affordable special characters and lords that can maul whole regiments, looking at you Mr. Bloodthirster. And you can always use Daemons in 40k. Granted Daemons are expensive due to 90% of the range being metal so can get to the expensive side but like I said your basically getting two armies for one price.